Climate - Bellingham (Washington_state)

The climate of Bellingham is sub-oceanic, with quite mild, rainy winters and mild, fairly sunny summers.
The city overlooks Bellingham Bay, which then opens onto the Strait of Georgia, where we find the San Juan Islands and then the Canadian island of Vancouver. We are in the far northwest of the United States, 25 km (15 mi) from the Canadian border. The Canadian city of Vancouver is located 65 km (40 mi) to the northwest. To the east, we find the mountains of the Mount Baker Ski Area.
The wind is frequent: during mild and rainy periods, the wind blows from the strait of Juan de Fuca, while during cold air outbreaks, it blows from the northeast after being channeled into the the Fraser River valley.
Although the winter is mild enough, there can sometimes be cold waves, sometimes even in November, with night temperatures going down to -10 °C (14 °F) or even below. For example, the temperature dropped to -18 °C (0 °F) in January 1950, to -15 °C (5 °F) in November 1955 and November 1985, and to -15.5 °C (4 °F) in February 1989.
Snow is quite rare: on average, 16 centimeters (6.5 in) per year. However, a fairly heavy snowfall can occur from time to time.
In summer, daytime temperatures are generally mild or pleasantly warm. However, there may also be hot periods, which last a few days, with highs of 32/33 °C (89/91 °F), and sometimes more. Generally, the heat is less intense than in Seattle, as we are more to the north. However, in July 2009, the temperature reached 36 °C (97 °F). In 2021, the temperature reached 37 °C (99 °F) in late June and 38 °C (100 °F) in August.
The average temperature of the coldest month (December) is of 4.3 °C (39.8 °F), that of the warmest months (July, August) is of 17.7 °C (63.9 °F). Here are the average temperatures.

Precipitation amounts to 880 millimeters (34.7 inches) per year: it is therefore not very abundant, though it is very frequent in the cold half of the year. It ranges from 20 mm (0.8 in) in the driest month (July) to 130 mm (5.1 in) in the wettest (November). Here is the average precipitation.

On average, there are around 1,865 sunshine hours per year. Bellingham is the least sunny city in the whole of the United States, although there's no big difference with Seattle and the other cities of the Puget Sound. Here are the average sunshine hours per day.

The sea temperature ranges between 7.5 °C (45.5 °F) and 13.5 °C (56.5 °F). So, it is cold all year round. Here are the average sea temperatures.

Best Time

The best time to visit Bellingham is summer, especially in July and August, since it is the mildest, driest and sunniest period of the year. June and September are also acceptable months.

Back to the climate of Washington state.

Bellingham - Weather by month

Based on the period 1991-2020

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In January, the weather in Bellingham is usually quite cold. The average temperature is of 4.5 °C (40 °F), with a minimum of 1.1 °C (34 °F) and a maximum of 7.9 °C (46.3 °F).
On the coldest nights of the month, the temperature usually drops to around -7 °C (19 °F). However, it dropped to -12.3 °C (9.9 °F) in January 1996.
On the warmest days of the month, the temperature usually reaches around 14 °C (57 °F). However, it reached 18.3 °C (64.9 °F) in January 2010.
Precipitation amounts to 115 mm (4.5 in), distributed over 19 days.
The day lasts on average 8 hours and 50 minutes.
There are on average 2 hours of sunshine per day. So, the sun shines 23% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 7.5 °C (46 °F). Therefore, the sea is very cold for swimming.

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In February, the weather in Bellingham is usually quite cold. The average temperature is of 5.4 °C (42 °F), with a minimum of 1.4 °C (34.5 °F) and a maximum of 9.4 °C (48.9 °F).
On the coldest nights of the month, the temperature usually drops to around -5 °C (23 °F). However, it dropped to -9.4 °C (15.1 °F) in February 2019.
On the warmest days of the month, the temperature usually reaches around 14.5 °C (58 °F). However, it reached 21.7 °C (71.1 °F) in February 2012.
Precipitation amounts to 70 mm (2.8 in), distributed over 16 days.
The day lasts on average 10 hours and 10 minutes.
There are on average 3 hours of sunshine per day. So, the sun shines 30% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 7.5 °C (45.5 °F). Therefore, the sea is very cold for swimming.

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In March, the weather in Bellingham is usually quite mild. The average temperature is of 7.3 °C (45 °F), with a minimum of 3.1 °C (37.5 °F) and a maximum of 11.6 °C (52.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -3 °C (27 °F). However, it dropped to -7 °C (19.4 °F) in March 2002.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 17.5 °C (64 °F). However, it reached 24.4 °C (75.9 °F) in March 2004.
Precipitation amounts to 85 mm (3.3 in), distributed over 18 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 4 hours of sunshine per day. So, the sun shines 33% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 8 °C (46.5 °F). Therefore, the sea is very cold for swimming.

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In April, the weather in Bellingham is usually mild. The average temperature is of 9.8 °C (50 °F), with a minimum of 5.3 °C (41.6 °F) and a maximum of 14.3 °C (57.7 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 0 °C (32 °F). However, it dropped to -3.3 °C (26.1 °F) in April 2008.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 22 °C (71.5 °F). However, it reached 28.3 °C (82.9 °F) in April 2016.
Precipitation amounts to 70 mm (2.8 in), distributed over 16 days.
The day lasts on average 13 hours and 50 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 43% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 9 °C (48.5 °F). Therefore, the sea is very cold for swimming.

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In May, the weather in Bellingham is usually mild. The average temperature is of 13.0 °C (55 °F), with a minimum of 8.3 °C (47 °F) and a maximum of 17.7 °C (63.9 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 2.5 °C (36.5 °F). However, it dropped to -0.6 °C (30.9 °F) in May 1999.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 25 °C (77.5 °F). However, it reached 30 °C (86 °F) in May 2016.
Precipitation amounts to 55 mm (2.2 in), distributed over 12 days.
The day lasts on average 15 hours and 20 minutes. So the days are long.
There are on average 7 hours of sunshine per day. So, the sun shines 46% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 11 °C (52 °F). Therefore, the sea is very cold for swimming.

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In June, the weather in Bellingham is usually very mild. The average temperature is of 15.4 °C (60 °F), with a minimum of 11 °C (51.8 °F) and a maximum of 19.9 °C (67.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 6.5 °C (43.5 °F). However, it dropped to 2.8 °C (37 °F) in June 1999.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 27 °C (80.5 °F). However, it reached 31.1 °C (88 °F) in June 1995.
Precipitation amounts to 40 mm (1.6 in), distributed over 10 days.
The day lasts on average 16 hours and 5 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 8 hours of sunshine per day. So, the sun shines 50% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 12.5 °C (54.5 °F). Therefore, the sea is very cold for swimming.

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In July, the weather in Bellingham is usually very mild. The average temperature is of 17.7 °C (64 °F), with a minimum of 12.8 °C (55 °F) and a maximum of 22.6 °C (72.7 °F).
On the coldest nights of the month, the temperature usually drops to around 8.5 °C (47 °F). However, it dropped to 5 °C (41 °F) in July 2000.
On the warmest days of the month, the temperature usually reaches around 29.5 °C (85 °F). However, it reached 36 °C (96.8 °F) in July 2009.
Precipitation amounts to 20 mm (0.8 in), distributed over 6 days.
The day lasts on average 15 hours and 35 minutes. So the days are long.
There are on average 9 hours of sunshine per day. So, the sun shines 58% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 13.5 °C (56.5 °F). Therefore, the sea is very cold for swimming.

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In August, the warmest month of the year, the weather in Bellingham is usually very mild. The average temperature is of 17.7 °C (64 °F), with a minimum of 12.6 °C (54.7 °F) and a maximum of 22.8 °C (73.1 °F).
On the coldest nights of the month, the temperature usually drops to around 8 °C (46 °F). However, it dropped to 5 °C (41 °F) in August 2000.
On the warmest days of the month, the temperature usually reaches around 29 °C (84.5 °F). However, it reached 32.2 °C (90 °F) in August 1993.
Precipitation amounts to 30 mm (1.2 in), distributed over 6 days.
The day lasts on average 14 hours and 10 minutes. So the days are long.
There are on average 8 hours of sunshine per day. So, the sun shines 56% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 13.5 °C (56.5 °F). Therefore, the sea is very cold for swimming.

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In September, the weather in Bellingham is usually very mild. The average temperature is of 14.9 °C (59 °F), with a minimum of 9.8 °C (49.6 °F) and a maximum of 20.1 °C (68.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 4 °C (39 °F). However, it dropped to 0.6 °C (33.1 °F) in September 2000.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 26.5 °C (79.5 °F). However, it reached 31 °C (87.8 °F) in September 2003.
Precipitation amounts to 50 mm (2 in), distributed over 11 days.
The day lasts on average 12 hours and 30 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 50% of the time.
The average humidity is 78%. Hence, the air is normally humid.
The average wind speed is 9 kph (5 mph).
The average sea temperature is of 13 °C (55 °F). Therefore, the sea is very cold for swimming.

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In October, the weather in Bellingham is usually mild. The average temperature is of 10.6 °C (51 °F), with a minimum of 6.2 °C (43.2 °F) and a maximum of 14.9 °C (58.9 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -0.5 °C (30.5 °F). However, it dropped to -5.6 °C (21.9 °F) in October 2002.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 21 °C (69.5 °F). However, it reached 24.4 °C (75.9 °F) in October 2020.
Precipitation amounts to 100 mm (3.9 in), distributed over 16 days.
The day lasts on average 10 hours and 40 minutes.
There are on average 4 hours of sunshine per day. So, the sun shines 38% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 11 °C (51.5 °F). Therefore, the sea is very cold for swimming.

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In November, the weather in Bellingham is usually quite mild. The average temperature is of 6.9 °C (44 °F), with a minimum of 3.3 °C (37.9 °F) and a maximum of 10.6 °C (51 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -4.5 °C (23.5 °F). However, it dropped to -11.1 °C (12 °F) in November 2006.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 16.5 °C (61.5 °F). However, it reached 22.8 °C (73 °F) in November 2016.
Precipitation amounts to 130 mm (5.1 in), distributed over 20 days.
The day lasts on average 9 hours and 5 minutes.
There are on average 2 hours of sunshine per day. So, the sun shines 22% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 9.5 °C (49 °F). Therefore, the sea is very cold for swimming.

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In December, the coldest month of the year, the weather in Bellingham is usually quite cold. The average temperature is of 4.3 °C (40 °F), with a minimum of 1.2 °C (34.1 °F) and a maximum of 7.5 °C (45.5 °F).
On the coldest nights of the month, the temperature usually drops to around -6.5 °C (20.5 °F). However, it dropped to -12.2 °C (10 °F) in December 1998.
On the warmest days of the month, the temperature usually reaches around 14 °C (57 °F). However, it reached 19.4 °C (66.9 °F) in December 2014.
Precipitation amounts to 110 mm (4.3 in), distributed over 19 days.
The day lasts on average 8 hours and 20 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 2 hours of sunshine per day. So, the sun shines 24% of the time.
The average humidity is 79%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 8.5 °C (47 °F). Therefore, the sea is very cold for swimming.